Presentation on theme: "Overview and Review of the Pelvis and Perineum"— Presentation transcript:
1 Overview and Review of the Pelvis and Perineum Biology 224Human Anatomy and Physiology - IIWeek 6; Lecture 2; WednesdayDr. Stuart S. SumidaOverview and Review of the Pelvis and PerineumThree-Dimensional Context for Excretory and Reproductive Systems
2 Pelvic girdle is suturally attached to axial skeleton to facilitate transmission of locomotor energy gnerated by legs to rest of body.
6 Major Landmarks You should remember: Iliac crestAnterior superior iliac spineAnterior inferior iliac spinePosterior superior iliac spinePosterior inferior iliac spineGreater sciatic notchSpine of ischiumLesser sciatic notchObturator foramen
12 Ligament running from sacrum to ischial tuberosity is SACROTUBEROUS LIGAMENT. Its presence closes off lesser sciatic notch to become lesser sciatic foramen.Ligament running from sacrum to ischial spine is SACROSPINOUS LIGAMENT. Its presence closes off greater sciatic notch to become greater sciatic foramen.
13 Ligament running from sacrum to ischial tuberosity is SACROTUBEROUS LIGAMENT. Its presence closes off lesser sciatic notch to become lesser sciatic foramen.Most, but not all of obturator foramen is covered over by obturator membrane. Smaller foramen is left.Ligament running from sacrum to ischial spine is SACROSPINOUS LIGAMENT. Its presence closes off greater sciatic notch to become greater sciatic foramen.
14 You should be able to draw it to this degree is detail. Piriformis muscle (important landmark)You should be able to draw it to this degree is detail.
15 Along with some other important things, the SCIATIC NERVE exits the pelvis through the greater sciatic foramen.
17 Review of Perineal Musculature. It is hypaxial musculature. Remember, always three layers:External Layer: Urogenital diaphragm (external sphincters) and deep transvese perineal muscleMiddle Layer: Pelvic diaphragmLevator aniCoccygeusIliococcygeus (more superficial and posterior)Pubococcygeus (more anterior)Deep Layer: Transversalis fasciaNerves run between middle and innermost layers.
21 MUSCULAR INNERVATION: Superficial layer: Pudendal nerve (S2,3,4) to urogenital diaphragm.Middle layer: Nerve to pelvic diaphragm (S4,5)Deep layer: reduced to fascia, no innervation necessary.
22 Muscle layers define important spaces: Deep perineal space lies internal to deepest layer (transversalis fascia).Ischiorectal fossa lies between urogenital diaphragm and pelvic diaphragm.Superficial perineal space is between urogenital diaphragm and superficial fascia plus skin.
23 Deep perineal spaceIschiorectal fossaSuperficial perineal space
24 Branches of the Internal Iliac Artery (In order) IliolumbarLateral sacralSuperior glutealInferior glutealInternal pudendalObturatorMiddle rectalInferior vesicleSuperior vesicleThe old umbilical artery connects to end of internal iliac.
25 Detail on Branches of Internal Iliac: Superior gluteal artery runs with superior gluteal nerve through greater sciatic foramen and over piriformis muscle.Inferior gluteal artery goes through grater sciatic foramen, but runs with inferior gluteal nerve and runs below piriformis muscle.(Internal) Pudendal artery travels with pudendal nerveObturator artery passes through obturator foramen.
26 Remember, terminal end of the internal iliac artery was the fetal umbilical artery. This means that you should be able to find it in continuity with the umbilicus via the MEDIAL UMBILICAL FOLD.